Attenuation of oxidative stress and alteration of hepatic tissue ultrastructure by D-pinitol in streptozotocin-induced diabetic rats

Abstract

The present study was aimed to investigate the effect of D-pinitol on hyperglycaemia mediated oxidative stress by analysing the hepatic antioxidant competence, pro-inflammatory cytokines and ultrastructural changes in liver tissues of streptozotocin-induced diabetic rats. Oral administration of D-pinitol (50 mg/kg b.w.) resulted in significant (p < 0.05) attenuation in blood glucose, glycosylated haemoglobin and pro-inflammatory markers such as TNF-α, IL-1β, IL-6, NF-κB p65 unit and NO and significant (p < 0.05) elevation in the plasma insulin level. In addition, D-pinitol instigated a significant escalation in the levels of hepatic tissue non-enzymatic antioxidants and the activities enzymatic antioxidants of diabetic rats with significant (p < 0.05) decrease in lipid peroxides and hydroperoxides formation, thus demonstrating the protective role of D-pinitol on the hepatic tissues from oxidative stress-induced liver damage. These biochemical observations were complemented by histological and ultrastructural examination of liver section. Thus, the present study demonstrates the hepatoprotective nature of D-pinitol by attenuating hyperglycaemia-mediated pro-inflammatory cytokines and oxidative stress.

Keywords::

• D-pinitol
• diabetes mellitus
• streptozotocin
• lipid peroxidation
• oxidative stress
• pro-inflammatory cytokines

Acknowledgement

The authors wish to record sincere thanks to Ms B. Rita and Mr P. Srinivasan, The Wellcome Trust Research Laboratory, Department of Gastrointestinal Sciences, Christian Medical College and Hospital, Vellore-632004, India, for their help in transmission electron microscopic and histopathological studies.

Declaration of interest: The research Fellowship of the University Grant Commission (UGC), New Delhi, India, to the first author, Mr S. Sivakumar, is gratefully acknowledged. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early Online on 30 March 2010.